<style>
    #app {
        padding-bottom: 60px;
    }
    .footer {
        position: fixed;
        width: 100%;
        bottom: 0;
        padding: 10px 0;
        background: #fff;
        z-index: 100;
    }
</style>
<div id="app">
    <p class="text-center" v-if="loading">加载中，请稍后</p>
    <el-tree
            :data="data"
            :props="{label: 'name', children: 'childlist'}"
            node-key="id"
            accordion
            :show-checkbox="true"
            :default-checked-keys="checkedKeys"
            :default-expanded-keys="[0]"
            @check="change">
    </el-tree>
    <div class="footer">
        <a class="btn btn-success" @click="submit">确定</a>
    </div>
</div>